Possible causes

– Low transmission fluid level
– Dirty transmission fluid
– Faulty 2-3 Shift Solenoid Valve
– 2-3 Shift Solenoid Valve harness or connectors
– 2-3 Shift Solenoid Valve circuit is open or shorted

When is the code detected?

When the Powertrain Control Module (PCM) detects a continuous open, short to ground or short to power in the 2-3 Shift Solenoid (SS) valve circuit, then DTC P0758 sets.

Symptoms

– Engine Light ON (or Service Engine Soon Warning Light)
– Transmission will not shift gears

P0758 GMC Description

The 2-3 Shift Solenoid (SS) valve controls the fluid flow acting on the 2-3 shift valves. The 2-3 SS valve is a normally-open exhaust valve that is used with the 1-2 SS valve in order to allow four different shifting combinations. The solenoid attaches to the control valve body within the transmission. The Powertrain Control Module (PCM) controls the solenoid by providing the ground path.